A modulator valve for an automatic transmission is controlled by pressure applied linearly by a push pin, and zero force is required to be applied to the push pin at idle throttle position and up to 15.5 pounds force at full throttle positions.
Due to manufacturing tolerances the relative position of the end of the push pin within each transmission varies and certain prior actuators for applying force to the push pin have not compensated for these variations and accordingly have failed to apply force to the push pin in direct proportion to the travel to the throttle. Further, such prior actuators have been so inefficient as to require application of force to the throttle at least equal to and sometimes in excess of the force applied to the push pin, thus increasing the required operating force.